Hanbongseong (漢峰城 Han Peak Wall)
Hanbong-seong reaches the top of Han Peak (Hanbong), southeast of the main wall built in 1624. It was constructed on the order of Oh Si-bok, the Defense Commander of the Defense Command at Namhan Mountain Fortress, in 1693, well after the Manchu invasion.
Sinnamseong (新南城 New South Wall)
This outer wall, also known as Namgyeokdae (南格臺) or Daebong (對峰 Opposing Peak), extends south from the 7th hidden gate (暗門) to the summit of Geomdan-san. The small, defensive installations known as Dondae (墩臺 observation tower) are placed at strategic points that could otherwise become liabilities to the main fortress. They are used as lookouts and help to prevent enemy reconnaissance or incursions. The dondae at Hanbong, east of Namhan Mountain Fortress, played a very important role in overall defense.
During the Manchu Invasion of 1636, this peak was used by the Qing forces to set up cannon that fired down on the fortress. According to historical records, this cannon fire even hit the roof of the temporary palace.
Bongamseong (蜂巖城 Bee Rock Wall)
"Bongamseong" refers to an outer wall section that runs northeast along a ridge from its east lookout to Bee Rock (Bong-am or Beol-bong), a 512.2m peak that is higher than the Namhan Mountain Fortress command post (at 497m). Thus, Bee Rock affords a wide view of the western section inside the fortress as well as its Eastern Wall. During the Manchu Invasion of 1636, the Qing forces seized Bee Rock and were able to ascertain the weaknesses inside the fortress. They also used the vantage point to direct their artillery fire. In 1686, a new wall was built to make up for this vulnerability. Work was begun on the 1st day of the 4th moon and completed on the 9th day of the 5th moon, some 40 days later. Bongamseong includes four hidden gates, two reinforced works, and a parapet.